Percutaneous Modified Blalock-Taussig Shunt Closure in a Patient with Isolated Right Ventricular Hypoplasia.

Clinical presentation, course, and treatment for patients with isolated right ventricular (RV) hypoplasia (IRVH) depends on the degree of hypoplasia that is present-this is a spectrum from spontaneous maturation to Fontan circulation over time. An 8-month-old infant presented with IRVH; in the patient, a modified Blalock-Taussig (MBTS) shunt was closed percutaneously after spontaneous RV function recovery. A female newborn was diagnosed with differential cyanosis at birth. The echocardiography showed a hypertrophic RV with a small cavity, a right-left shunt on the atrial septal defect, an almost closed ductus arteriosus (DA), and a small tricuspid valve ring (Z-score-2) with mild regurgitation (pressure gradient 30 mmHg). On the 4th day of life, the patient showed deepened cyanosis and hyperlactatemia was registered. The echocardiography examination revealed a closed DA. Right ventriculography performed on the 5th day of life evidenced the presence of a small hypertrabeculated RV. The pressure in the RV increased. A right-side MBTS was created on the 6th day of life. Further echocardiographic findings indicated a gradual development of the RV and a decrease in RV pressure. MBTS occlusion was performed when the patient was 8 months old. Vital parameters were monitored invasively and noninvasively after the balloon occlusion of MBTS. Percutaneous MBTS occlusion was successfully performed using an Amplatzer vascular plug 2 (AVP2). During the follow-up period, the patient was found to have maintained a normal percutaneous oxyhaemoglobin blood saturation.

Mechanisms of redox balance and inflammatory response after the use of methylprednisolone in children with multisystem inflammatory syndrome associated with COVID-19.

Background: Multisystem inflammatory syndrome in children (MIS-C) associated with being infected with coronavirus-19 (COVID-19) is a life-threatening condition resulting from cytokine storm, increased synthesis of reactive oxygen species (ROSs), and hyperinflammation occurring in genetically predisposed children following an infection with SARS-CoV-2. Aim: The primary aims of our study were to identify changes in the activity of antioxidant enzymes in erythrocytes and total oxidative status in plasma after being treated with methylprednisolone (MP). Methods: A prospective cohort study of 67 children (56.7% male) under 18 with MIS-C being treated with MP was conducted at the Mother and Child Health Institute from January 2021 to April 2022. The impact of the therapy was assessed on the basis of the clinical condition, haematological and biochemical blood parameters, and echocardiographic findings. Results: 59.7% of patients presented cardiovascular (CV) manifestations, while myocardial dysfunction was observed in half of all patients (50.7%). A severe clinical course was observed in 22/67 patients. Children with CV involvement had a significantly higher relative concentration of B lymphocytes and lower relative concentration of NK cells than patients without CV issues (p < 0.001 and p = 0.004, respectively). Patients with severe MIS-C had a lower relative count of NK cells than those with moderate MIS-C (p = 0.015). Patients with myocardial dysfunction had a higher total oxidative plasma status (TOPS) than children without (p = 0.05), which implicates pronounced oxidative stress in the former cohort. In patients with shock, lower erythrocytes superoxide dismutase (SOD) activity was observed on admission compared to patients without shock (p = 0.04). After MP was administered, TOPS was significantly reduced, while catalase (CAT) and SOD activity increased significantly. Treatment failure (TF) was observed in 6 patients, only females (p=0.005). These patients were younger (p=0.05) and had lower CAT activity on admission (p=0.04) than patients with favorable treatment responses. In the group of patients with TF, TOPS increased after treatment (before 176.2 ± 10.3 mV, after 199.0 ± 36.7 mV). Conclusion: MP leads to rapid modulation of TOPS and increases the activity of antioxidant enzymes in erythrocytes resulting in clinical and echocardiographic improvement. Based on the observed changes in the activity of the antioxidant enzymes, we can conclude that s hydrogen peroxide is the dominant ROS in patients with MIS-C. Patients with TF showed reduced CAT activity, whereas the treatment with MP led to pronounced oxidation. This implies that low CAT activity may be a contraindication for using MP.

Analysis of cardiac manifestation and treatment of multisystem inflammatory syndrome in children related to SARS-CoV-2.

Cardiovascular manifestations are common (35-100%) in the multisystem inflammatory syndrome in children. Our study aimed to analyze treatment impact and cardiovascular involvement in patients with multisystem inflammatory syndrome in children. The retrospective cohort included 81 patients treated between April 2020 and December 2021 (9.3±4.6 years). Elevated cardiac troponin I and pro-B-type natriuretic peptide were observed in 34.2% and 88.5% of patients, respectively. Myocardial dysfunction was observed in 50.6%. Children older than 10 years had a 4-fold increased risk of myocardial dysfunction (odds ratio [OR] 3.6, 95% confidence interval [CI] 1.4-8.9; p=0.006). A moderate negative correlation was proved between left ventricle ejection fraction and C-reactive protein (rr = - 0.48; p < 0.001). More than one-fifth of the patients presented with shock. Coronary artery dilatation was observed in 6.2% of patients. Mild pericardial effusion was detected in 27.1% of children. On standard electrocardiogram, 52.6% of children had negative T waves in the inferior and/or precordial leads; transient QTc prolongation was registered in 43% of patients. Treatment failure was observed in 19 patients. Patients initially treated with intravenous immunoglobulins had 10-fold higher chances for treatment failure than patients treated with corticosteroids (OR 10.6, 95% CI 3,18 - 35.35; p < 0.001). Cardiovascular manifestations were observed in more than half of the patients, with acute myocardial dysfunction being the most common, especially in children older than 10 years. We established a negative association between the degree of elevation of inflammatory markers and left ventricular ejection fraction. Patients treated with intravenous immunoglobulins who had cardiovascular manifestations had treatment failures more frequently than patients treated with corticosteroids.

Developing COVID-19 vaccine recommendations during the pandemic: The experience of Serbia's Expert Committee on Immunization.

A National Immunization Technical Advisory Group (NITAG) is a multi-disciplinary body of national experts that provide evidence-based recommendations to policy-makers to assist them in making informed immunization policy and programme decisions. During the COVID-19 pandemic, NITAGs faced many challenges in making evidence-based recommendations for COVID-19 vaccines due to the rapidly evolving situation with new vaccine products available in a short time period and limited data on vaccine effectiveness. The authors reviewed the process used by Serbia's NITAG, which is called the Serbian Expert Committee on Immunization, to develop COVID-19 vaccine recommendations during the pandemic. The article examines the challenges and successes faced by the committee. Serbia's expert committee used the best available evidence to develop over forty recommendations on all aspects of COVID-19 vaccination. These expert committee recommendations facilitated the early procurement and successful roll-out of COVID-19 vaccines, guidance for vaccination of individuals at the highest risk, and high COVID-19 vaccination coverage in the country. The availability of five COVID-19 vaccines in Serbia was an advantage for the successful roll-out but posed challenges for the expert committee. Serbia's expert committee plans to use the experience and best practices developed during the pandemic to improve and expand its work moving forward.

Could the unfortunate outcome of pediatric acute myocarditis be predicted? Factors contributing to a poor outcome in myocarditis.

OBJECTIVE: Myocarditis has spontaneous resolution in 50% of patients. Our study aimed to define risk factors for developing dilated cardiomyopathy (DCM) and death in pediatric patients with acute myocarditis (AM). METHODS: The retrospective cohort study included all patients with treated AM. The Mother and Child Health Institute from January 2011 to March 2019. RESULTS: In the study, 62 patients were included, 40 boys and 22 girls (11.15±5.86 years) with AM. Twelve out of sixty-two children had acute fulminant myocarditis. Four patients died in the acute phase of AM, and 11 developed DCM. Follow up was 27.14±36.52 months. Patients with poor outcome (DCM development) were under the age of seven (odds ratio [OR] 10.1; p=0.003), more likely to be girls (OR 4.6; p=0.03), and had fulminant myocarditis (OR 27.0; <0.001). An ejection fraction (EF) <55% and fractional shortening (FS) <30% increased risk of DCM 13- and 5-fold, respectively, but patients with EF between 40 and 55% remain at highest risk of developing DCM. There was a 12-fold increased risk for DCM in patients with left ventricular end-diastolic diameter Z score >2+. The receiver operator curve showed that the lactate dehydrogenase (LDH) cut-off value for developing DCM was 1780 mmol/l (sensitivity 80%, specificity 100%). CONCLUSION: Acute fulminant myocarditis was an independent risk factor for DCM. Children with EF between 40 and 50% at admission were at highest risk of developing DCM. Lactate dehydrogenase value could be a significant prognostic value for the outcome of pediatric myocarditis.

Recent Experience: Corticosteroids as a First-line Therapy in Children With Multisystem Inflammatory Syndrome and COVID-19-related Myocardial Damage.

BACKGROUND: Cardiovascular complications with myocarditis in multisystem inflammatory syndrome in children (MIS-C) associated with severe acute respiratory syndrome coronavirus 2 infection have been reported, but the optimal therapeutic strategy remains unknown. METHODS: A retrospective cohort study included 19 patients with acute left ventricular systolic dysfunction associated with MIS-C, average years of age 13.2 ± 3.8, treated from April 2020 to April 2021. RESULTS: Treatment failure (TF) was observed in 8 patients (in the intravenous immunoglobulin [IVIG] group 7/10; in the corticosteroid [CS] group 1/9). The independent risk factor for TF was IVIG treatment (odds ratio [OR] 18.6, 95% confidence interval [CI] 1.6-222.93, P = 0.02). Patients initially treated with CS became afebrile during in-hospital day 1 (1.5, interquartile range [IQR] 1-2), while IVIG-treated patients became afebrile on in-hospital day 4 (IQR 2-4.25), after CS was added. The C-reactive protein (CRP) significantly declined in CS-treated patients on day 2 (P = 0.01), while in the IVIG group, CRP decreased significantly on the fourth day (P = 0.04). Sodium and albumin levels were higher on third in-hospital day in the CS group than in the IVIG group (P = 0.015, P = 0.03). A significant improvement and normalization of ejection fraction (EF) during the first 3 days was observed only in the CS group (P = 0.005). ICU stays were shorter in the CS group (4, IQR 2-5.5) than in the IVIG group (IVIG group 7, IQR 6-8.5) (P = 0.002). CONCLUSIONS: Among children with MIS-C with cardiovascular involvement, treatment with CS was associated with faster normalization of LV EF, fever, laboratory analysis, and shorter ICU than IVIG-treated patients.

Predictive factors of recurrence after pediatric acute pericarditis

Abstract Objective The predisposing factors for pericarditis recurrence in the pediatric population have not yet been established. This study aimed to define the risk factors for the unfavorable prognosis of pediatric acute pericarditis. Methods This was a retrospective study that included all patients with acute pericarditis treated from 2011 to 2019 at a tertiary referent pediatric center. Results The study included 72 children. Recurrence was observed in 22.2% patients. Independent risk factors for recurrence were: erythrocyte sedimentation rate ≥ 50 mm/h (p = 0.003, OR 186.3), absence of myocarditis (p = 0.05, OR 15.2), C-reactive protein ≥ 125 mg/L (p = 0.04, OR 1.5), and non-idiopathic etiology pericarditis (p = 0.003, OR 1.3). Corticosteroid treatment in acute pericarditis was associated with a higher recurrence rate than treatment with non-steroid anti-inflammatory therapy (p = 0.04). Furthermore, patients treated with colchicine in the primary recurrence had lower recurrence rate and median number of repeated infections than those treated without colchicine (p = 0.04; p = 0.007, respectively). Conclusion Independent risk factors for recurrence are absence of myocarditis, non-idiopathic etiology pericarditis, C-reactive protein ≥ 125 mg/L, and erythrocyte sedimentation rate ≥ 50 mm/h. Acute pericarditis should be treated with non-steroid anti-inflammatory therapy. A combination of colchicine and non-steroid anti-inflammatory drugs could be recommended as the treatment of choice in recurrent pericarditis.

Differences Between Pediatric Acute Myocarditis Related and Unrelated to SARS-CoV-2.

BACKGROUND: Acute myocarditis (AM) is defined as inflammation of the myocardium. The aim of our study is a comparative analysis of the differences between AM related and unrelated to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). METHODS: The retrospective study included children with AM treated from January 2018 to November 2020. RESULTS: The study included 24 patients; 7 of 24 had AM related to SARS-CoV-2 and they were older than 7. They were more likely to have abdominal pain (P = 0.014), headache (P = 0.003), cutaneous rash (P = 0.003), and conjunctivitis (P = 0.003), while fulminant myocarditis was commonly registered in AM unrelated to SARS-CoV-2 (P = 0.04). A multisystem inflammatory syndrome in children associated with COVID-19 was diagnosed in six adolescents. Patients with AM related SARS-CoV-2 had lower serum cardiac troponin I (cTnI) (P = 0.012), and platelets (P < 0.001), but had a higher C-reactive protein (CRP) value (P = 0.04), and N-terminal-pro hormone BNP in comparison to patients with AM unrelated to SARS-CoV-2. The patients with AM related to SARS-CoV-2 had significant reduction of CRP (P = 0.007). Inotropic drug support was used for shorter durations in patients with AM related to SARS-CoV-2, than in others (P = 0.02). Children with AM related to SARS-CoV-2 had significant improvement of left ventricle systolic function on the third day in hospital (P = 0.001). Patients with AM unrelated to SARS-CoV-2 AM had more frequent adverse outcomes (P = 0.04; three died and four dilated cardiomyopathy). CONCLUSIONS: In contrast to patients with AM unrelated to SARS-CoV-2, patients with AM related to SARS-CoV-2 had a higher CRP value, polymorphic clinical presentation, shorter durations of inotropic drugs use as well as prompt recovery of left ventricle systolic function.

Predictive factors of recurrence after pediatric acute pericarditis.

OBJECTIVE: The predisposing factors for pericarditis recurrence in the pediatric population have not yet been established. This study aimed to define the risk factors for the unfavorable prognosis of pediatric acute pericarditis. METHODS: This was a retrospective study that included all patients with acute pericarditis treated from 2011 to 2019 at a tertiary referent pediatric center. RESULTS: The study included 72 children. Recurrence was observed in 22.2% patients. Independent risk factors for recurrence were: erythrocyte sedimentation rate≥50mm/h (p=0.003, OR 186.3), absence of myocarditis (p=0.05, OR 15.2), C-reactive protein≥125mg/L (p=0.04, OR 1.5), and non-idiopathic etiology pericarditis (p=0.003, OR 1.3). Corticosteroid treatment in acute pericarditis was associated with a higher recurrence rate than treatment with non-steroid anti-inflammatory therapy (p=0.04). Furthermore, patients treated with colchicine in the primary recurrence had lower recurrence rate and median number of repeated infections than those treated without colchicine (p=0.04; p=0.007, respectively). CONCLUSION: Independent risk factors for recurrence are absence of myocarditis, non-idiopathic etiology pericarditis, C-reactive protein≥125mg/L, and erythrocyte sedimentation rate≥50mm/h. Acute pericarditis should be treated with non-steroid anti-inflammatory therapy. A combination of colchicine and non-steroid anti-inflammatory drugs could be recommended as the treatment of choice in recurrent pericarditis.

Myocardial damage in multisystem inflammatory syndrome associated with COVID-19 in children and adolescents.

BACKGROUND: In multisystem inflammatory syndrome in children (MIS-C) temporarily associated with coronavirus disease-19 (COVID-19), myocardial damage has been reported. MATERIALS AND METHODS: A retrospective observational cohort study included children under 18 who had a myocardial injury related to COVID-19 treated in mother and child health institute from April 2020 to August 2020. Myocardial injury related to COVID-19 was manifested by elevated serum cardiac troponin and NT-proBNP with LV dysfunction, arrhythmias, and coronary arteries (CAs) dilatation or aneurysms. During the short-term follow-up, cardiac testing (electrocardiography, laboratory analysis, echocardiography, 24-h Holter monitoring, exercise stress test, and cardiac magnetic resonance) was performed. RESULTS: Six male adolescents (14.7 ± 2.4 years) were included in the analysis (2/6 had MIS-C shock syndrome). All patients had elevated acute-phase reactants and NT-proBNP, whereas troponins were elevated in 5/6 patients. Echocardiography revealed left ventricular (LV) systolic dysfunction (EF 45.2 ± 6.9%); 2/6 had dilated CAs. IVIG was prescribed to all patients with MIS-C. Four patients required inotropic drug support. During hospitalization, a significant reduction of CRP, LDH, NT-proBNP, and D-dimer (P < 0.05) was registered. LV systolic function recovery was registered 3 days after applied therapy (P < 0.001). None of the patients developed dilated cardiomyopathy or CA aneurysms. CONCLUSIONS: With early recognition and adequate MIS-C therapy, children recovered entirely, maintained in the short-term follow-up period.

European Society of Cardiology Working Group on Adult Congenital Heart Disease and Study Group for Adult Congenital Heart Care in Central and South Eastern European Countries consensus paper: current status, provision gaps and investment required.

AIMS: To examine the current status of care and needs of adult congenital heart disease (ACHD) services in the Central and South Eastern European (CESEE) region. METHODS AND RESULTS: We obtained data regarding the national ACHD status for 19 CESEE countries from their ACHD representative based on an extensive survey for 2017 and/or 2018. Thirteen countries reported at least one tertiary ACHD centre with a median year of centre establishment in 2007 (interquartile range 2002-2013). ACHD centres reported a median of 2114 patients under active follow-up with an annual cardiac catheter and surgical intervention volume of 49 and 40, respectively. The majority (90%) of catheter or surgical interventions were funded by government reimbursement schemes. However, all 19 countries had financial caps on a hospital level, leading to patient waiting lists and restrictions in the number of procedures that can be performed. The median number of ACHD specialists per country was 3. The majority of centres (75%) did not have ACHD specialist nurses. The six countries with no dedicated ACHD centres had lower Gross Domestic Product per capita compared to the remainder (P = 0.005). CONCLUSION: The majority of countries in CESEE now have established ACHD services with adequate infrastructure and a patient workload comparable to the rest of Europe, but important gaps still exist. ACHD care is challenged or compromised by limited financial resources, insufficient staffing levels, and reimbursement caps on essential procedures compared to Western Europe. Active advocacy and increased resources are required to address the inequalities of care across the continent.

Kawasaki-like disease and acute myocarditis in the SARS-CoV-2 pandemic - reports of three adolescents.

The novel coronavirus disease (COVID-19) may induce multisystem inflammatory syndrome (MIS) in children, which may be associated with Kawasaki-like disease and cardiac injury. In this study, we presented three male adolescents with MIS and myocardial injury admitted to the hospital during the peak of COVID-19 pandemic. All of the three patients had a history of fever, gastrointestinal symptoms, polymorph rash, non-exudative  onjunctivitis, and signs of acute myocarditis (AM). One of them had renal failure. Previously, they did not have an acute infection. Upon admission, they were hypotensive and tachycardic. A nasopharyngeal swab for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on reverse transcription-polymerase chain reaction (PCR) assay was negative, but neutralizing viral antibodies were positive. In combination with blood tests,  lectrocardiogram, echocardiography, and computerized tomography, a MIS associated with acute myocarditis with mild to moderate systolic dysfunction and dilated coronary arteries were diagnosed. Two of three patients had shock syndrome andrequired inotropic support. All patients were treated with intravenous imunoglobulins (Ig). The second patient had a fever up to 102.2°F (39°C) 3 days after intravenous Ig. Further, he was treated according to protocols for refractory Kawasaki disease, with an intravenous methylprednisolone pulse therapy and aspirin. After a few hours, he became afebrile and the clinical signs disappeared. The favorable short-term outcome may reflect early recognition and adequate therapy; however, the long-term outcomes are currently unknown.

The features of neonatal seizures as predictors of drug-resistant epilepsy in children.

PURPOSE: The aim of this study was to evaluate the predictive value of the features of neonatal seizures for pharmacoresistant epilepsy in children. METHOD: This is a retrospective study that involved all children diagnosed as having epilepsy who had neonatal seizures and who were hospitalized at the Neurology Department of the Mother and Child Healthcare Institute in Belgrade from January the 1st 2017 until December 31st 2017. The following parameters and their impact on the outcome were investigated: perinatal data, the characteristics of epileptic seizures in the neonatal period, and the response to anticonvulsant treatment. The presence of pharmacoresistance was observed as an outcome parameter. Univariate and multivariate logistic regression analyses were used to define predictors of drug-resistant epilepsy. RESULTS: The study involved 55 children, 35 (63.6%) male and 20 (36.4%) female. The average age of the children at the end of the observation period was 5.17 years (min: 0.25, max: 17.75, iqr (interquartile range): 6.92). Pharmacoresistant epilepsy was found in 36 (65.5%) children. The most common type of epilepsy was focal, which affected 30 patients (54.5%), than generalized, which affected 15 patients (27.3%), and combined generalized and focal, which affected 8 patients (14.5%). At the end of the observation period, 28 patients (50.9%) had no seizures, while 14 (25.5%) had daily seizures. It was found that the pharmacoresistant neonatal seizures and metabolic-genetic disorders were predictive factors of the occurrence of pharmacoresistant epilepsy. CONCLUSION: Patients prone to developing pharmacoresistant epilepsy might be identified as early as the neonatal and early infant period. High incidence of asphyxia cooccurring with established genetic-metabolic disease further emphasizes need for genetic testing in infants with neonatal seizures including in the presence of hypoxic-ischemic injury.

Does Colchicine Substitute Corticosteroids in Treatment of Idiopathic and Viral Pediatric Pericarditis?

Background and Objectives: Recurrence of pericarditis (ROP) is an important complication of the acute pericarditis. The aim of this study was to analyse the influence of aetiology, clinical findings and treatment on the outcome of acute pericarditis. Methods: Data were retrospectively collected from medical records of patients treated from 2011 to 2019 at a tertiary referent heart paediatric center. Results: Our investigation included 56 children with idiopathic and viral pericarditis. Relapse was registered in 8/56 patients, 2/29 (7.41%) treated with nonsteroidal anti-inflammatory drugs (NSAID) and 6/27 (28.57%) treated with corticosteroids (CS) and NSAID. Independent risk factors for ROP were viral pericarditis (p = 0.01, OR 31.46), lack of myocardial affection (p = 0.03, OR 29.15), CS use (p = 0.02, OR 29.02) and ESR ≥ 50 mm/h (p = 0.03, OR 25.23). In 4/8 patients the first recurrence was treated with NSAID and colchicine, while treatment of 4/8 patients included CS. Children with ROP treated with CS had higher median number of recurrence (5, IQR: 2-15) than those treated with colchicine (0, IQR: 0-0.75). Conclusions: Independent risk factors for recurrence are CS treatment, viral aetiology, pericarditis only and ESR ≥ 50 mm/h. Acute pericarditis should be treated with NSAID. Colchicine and NSAID might be recommended in children with the first ROP.

Long-term outcome in children with neonatal seizures: A tertiary center experience in cohort of 168 patients.

PURPOSE: The purpose of this study was to evaluate long-term outcome and assess predictors of prognosis in children with neonatal seizures (NS). METHOD: This retrospective study includes children with NS treated at our Institute from January the 1st 2005 until December the 31st 2015. The data were collected from medical charts and the electroencephalogram (EEG) database at the Institute. The predictive value was evaluated for following parameters: (1) characteristics of the patients, such as gender, gestational age, birth body weight, Apgar score, artificial ventilation; (2) etiology; (3) characteristics of seizures such as type, time of onset, resistance to treatment; and (4) EEG background activity and paroxysmal discharges. The outcome of NS was assessed at the end of the follow-up period and was categorized as one of the following: (1) lethal outcome, (2) neurological abnormalities, (3) intellectual disability, and (4) epilepsy. Univariate and multivariate logistic regression analyses were used to assess predictors of NS outcome. RESULTS: The study included 168 children with NS (of which 109 are males, and 59 are females), mean aged 5.6 (SD 3.5) years at the end of the follow-up (with a range of 1 to 12 years). There was normal neurological development without epilepsy in 131 patients (78%), neurological abnormality in 31 (19.0%), intellectual disability in 28 (17.2%), epilepsy in 12 (7.4%), and lethal outcome in 7 patients (4.17%). CONCLUSIONS: Long-term outcome in children with NS could be favorable in most patients, and it appears to be related to specific early clinical and paraclinical variables. Newborns with an abnormal background EEG activity, with seizures resistant to antiepileptic drugs and/or low Apgar score are at a higher risk of a poor outcome. Females are at a much higher risk of lethal outcome than males.

Reproducibility of 24-h heart rate variability in children.

BACKGROUND: Over the last decades, time domain heart rate (HR) variability analysis has been explored in different pediatric clinical settings to obtain information on the cardiac autonomic tone. However, the consistency over time of 24 h time domain HRV measurements in children is not well-known. METHODS: We investigated the reproducibility of 24 h HRV time-domain indices (1 day apart), from 39 healthy children (9.5 ± 5.3 years, 56.4% girls). The parameters analysed included: standard deviation of all the adjacent NN intervals, standard deviation of the averages of NN intervals (the intervals between normal R-peaks) in all 5-min segments, and square root of the mean of the sum of the squares of the differences between adjacent NN intervals, uncorrected and corrected for HR. Reproducibility between two 24-h ECG recordings was evaluated by intraclass correlation coefficients, standard error of measurement, coefficients of variation and Bland-Altman plots. RESULTS: For the analyzed time-domain indices, standard deviation of all the adjacent NN intervals corrected for HR showed best reproducibility with the highest intraclass correlation coefficient (0.987), the lowest coefficients of variation (5.5%) and the best level of agreement between two recordings as assessed by Bland-Altman plots. CONCLUSIONS: Our results indicate that the standard deviation of all the adjacent NN intervals corrected for the HR parameter obtained from 24-h ambulatory recordings in children is consistent and reproducible over time, thus allowing reliable identification of cardiac autonomic tone in this age group.

Successful use of sirolimus for refractory atrial ectopic tachycardia in a child with cardiac rhabdomyoma.

Cardiac rhabdomyomas are common in tuberous sclerosis. We report a child who developed rhabdomyoma related arrhythmia refractory to antiarrhythmic drug therapy. Reversion of the atrial ectopic tachycardia was achieved with mammalian target of rapamycin pathway (mTOR) inhibitor sirolimus. As per our knowledge, this is the first time that sirolimus has been successfully used in this setting.